When you think about Arizona's landscape, the saguaro cactus is one of the quintessential images that come to mind — and Saguaro National Park, the subject of our March issue, celebrates this iconic Arizona plant. Saguaros are rarely symmetrical, but on even rarer occasions, an anomaly causes the tips to grow in a splayed, fan-like shape. These are the elusive crested saguaros — also known as cristate saguaros. It's not known why this mutation occurs, although scientists have a few theories.

Joe Pleggenkuhle and other saguaro enthusiasts joined forces to create the Crested Saguaro Society, dedicated to locating, cataloging and teaching people about these rare saguaros. We asked him a few questions about his passion. (This interview has been condensed and edited for clarity.)

When was the first time you came across a crested saguaro?
My first crested saguaro I saw was on a tour of the Phoenix Desert Botanical Garden. My first wild crested saguaro I found was in Yavapai County — it's a double crested saguaro. My niece had heard that I found a champion saguaro, and she wanted to see it, so I showed it to her. I was explaining to her that there were crested saguaros, too, and she points over my shoulder and says, “You mean like that?”

I had never heard of a double crested saguaro, so I started writing several places, and I believe Arizona Highways sent me an article that included a double crested saguaro many years ago.

When you first saw the one on the tour, did you know what it was right away?
No, but the tour guide did a great job of explaining what it was.

What are some of the theories about what causes this mutation to happen?
Many theories of what causes it. Frost; insect infestation; damage from birds, animals, people, weather, power lines. Mine is that the top or tip's growth pattern gets disturbed, and it changes from a circle to being elongated with a seam.

How many of these saguaros has the society cataloged?
Roughly 3,000. More if you count other crested cactuses.

How many in Saguaro National Park?
I’ve heard 48, but I suspect there are more than that in both the east and west parks and in Tucson Mountain Park.

How did the Crested Saguaro Society get started? 
That’s a good question. A person in Tucson was documenting them, and his health was declining, and a couple from the Southern Arizona hiking club sort of picked up where he had left off. They soon were giving presentations of their crested saguaro finds to their club. One of the other members, Rex, sort of got us together and named us the Crested Saguaro Society.

There isn’t a lot of information as to where people can find a crested saguaro; is there a reason?
We do love our crested saguaros, but several have been dug up or vandalized, so we don’t publish GPS locations of any of them. A fair amount of them are on private property. Some are located in steep, remote canyons.

— Roman Russo

To learn more about the Crested Saguaro Society or get involved with the group, visit its website.